CA2295760C - Battery pack and method for connecting battery modules - Google Patents

Battery pack and method for connecting battery modules Download PDF

Info

Publication number
CA2295760C
CA2295760C CA002295760A CA2295760A CA2295760C CA 2295760 C CA2295760 C CA 2295760C CA 002295760 A CA002295760 A CA 002295760A CA 2295760 A CA2295760 A CA 2295760A CA 2295760 C CA2295760 C CA 2295760C
Authority
CA
Canada
Prior art keywords
battery modules
positive
negative
battery
battery pack
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CA002295760A
Other languages
French (fr)
Other versions
CA2295760A1 (en
Inventor
Robert B. Field
Vladimir S. Pavlovic
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ecotality Inc
Original Assignee
Edison Source
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Edison Source filed Critical Edison Source
Publication of CA2295760A1 publication Critical patent/CA2295760A1/en
Application granted granted Critical
Publication of CA2295760C publication Critical patent/CA2295760C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M6/00Primary cells; Manufacture thereof
    • H01M6/50Methods or arrangements for servicing or maintenance, e.g. for maintaining operating temperature
    • H01M6/5011Methods or arrangements for servicing or maintenance, e.g. for maintaining operating temperature for several cells simultaneously or successively
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/42Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/4207Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells for several batteries or cells simultaneously or sequentially
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/50Current conducting connections for cells or batteries
    • H01M50/502Interconnectors for connecting terminals of adjacent batteries; Interconnectors for connecting cells outside a battery casing
    • H01M50/503Interconnectors for connecting terminals of adjacent batteries; Interconnectors for connecting cells outside a battery casing characterised by the shape of the interconnectors
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M6/00Primary cells; Manufacture thereof
    • H01M6/50Methods or arrangements for servicing or maintenance, e.g. for maintaining operating temperature
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00Circuit arrangements for charging or discharging batteries or for supplying loads from batteries
    • H02J7/50Circuit arrangements for charging or discharging batteries or for supplying loads from batteries acting upon multiple batteries simultaneously or sequentially
    • H02J7/52Circuit arrangements for charging or discharging batteries or for supplying loads from batteries acting upon multiple batteries simultaneously or sequentially for charge balancing, e.g. equalisation of charge between batteries
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/42Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M6/00Primary cells; Manufacture thereof
    • H01M6/42Grouping of primary cells into batteries
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Power Engineering (AREA)
  • Battery Mounting, Suspending (AREA)
  • Secondary Cells (AREA)

Abstract

A battery pack and method for connecting battery modules to optimize current sharing and charging of the modules. The battery pack comprises a number of battery modules, each module having respective positive and negative terminals. Interconnecting cables are provided for connecting the respective positive terminals and the respective negative terminals. The interconnecting cables have equal electrical lengths so that the Ohmic resistance is the same for the cables. The battery modules are also arranged in close proximity to form an isothermal zone.

Description

TITLE: BATTERY PACK AND METHOD FOR CONNECTING
BATTERY MODULES
FIELD OF THE INVENTION
This invention relates to batteries, and more particularly to a method for interconnecting battery modules in parallel to form a rechargeable battery pack.
BACKGROUND OF THE INVENTION
The popularity of rechargeable batteries is increasing and the number of applications keeps growing.
With the growing number of applications, demands are being put on the capacity requirements of the rechargeable batteries. To meet the capacity requirements, battery packs are being utilized. A battery pack comprises a number of lower capacity battery modules which are connected together in parallel to provide the increased output.
In conventional battery packs, the battery modules are typically connected in individual strings to obtain the desired voltage and then the individual strings are connected in parallel. Alternatively, the battery modules are connected in parallel without regard to current sharing. It will appreciated by those skilled in the art that the current sharing capability of battery packs is critical to the efficient recharging of the battery packs.
While existing battery pack configurations provide an increased output, there remains a need to improve the current sharing between the battery modules.
The problem of current sharing becomes particularly acute in applications and recharging cycles where high currents are being utilized.
BRIEF SUMMARY OF THE INVENTION
The present provides an arrangement for interconnecting battery modules to optimize current sharing between modules. The optimal current sharing achieved by the interconnection arrangement according to the present invention improves considerably the charging performance and capacity of the battery modules., According to the present invention, a multiple capacity battery pack is formed by connecting single modules in parallel rather connecting strings of battery modules in parallel. It is a feature of the present invention that interconnection resistance for every module is equal which, in turn, provides balanced current sharing.
Balanced current sharing is desirable in the context of fast, i . a . high current rate, recharging so that one or more of the battery modules is not overcharged and possibly damaged. In other words, the equal resistance of the interconnection allows the charging current to be shared by the modules on an as accepted basis. The charging current is not forced into a battery module at a rate at which the module is not able to accept.
In a first aspect, the present invention provides a battery pack comprising: (a) a plurality of battery modules, each of said battery modules having a positive terminal and a negative terminal; (b) positive interconnecting cables for connecting the positive terminal of each of said battery modules; (c) negative interconnecting cables for connecting the negative terminal of each of said battery modules; (d) a negative output cable coupled to the negative terminal of one of said battery modules; (e) a positive output cable couples to the positive terminal of one of said battery modules; (f) wherein said positive and negative interconnecting cables each have the same length; and (g) wherein said positive and negative output cables have the same length.

In a second aspect, the present invention provides a method for forming a battery pack from a plurality of battery modules, said method comprising the steps of: positioning the battery modules in close proximity to each other; interconnecting the respective positive terminals on the battery modules with interconnecting cables of the same length; interconnecting the respective negative terminals on the battery modules with interconnecting cables of the same length.
In another aspect, the present invention provides a battery pack comprising: (a) a plurality of battery modules, each of said battery modules having a positive terminal and a negative terminal; (b) positive interconnecting cables for connecting the positive terminal of each of said battery modules; (c) negative interconnecting cables for connecting the negative terminal of each of said battery modules; (d) a negative output cable coupled to the negative terminal of one of said battery modules; (e) wherein said positive and negative interconnecting cables each have the same Ohmic resistance.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made to the accompanying drawings which show, by way of example, a preferred embodiment of the present invention and in which:
Fig. 1 is a schematic view of a battery connection arrangement according to the present invention;
Fig. 2 is a schematic view of the resultant interconnection resistance for the connection arrangement of Fig : 1.

DETAILED DESCR ~TION OF THE PREFERRED EMBODIMENT
Reference is first made to Fig. 1 which shows a battery pack 1 according to the present invention.
The battery pack 1 comprises a number of individual battery modules 3 , shown individually as 3a, 3b, 3c. The battery modules 3 are connected in parallel at the positive terminals by interconnecting leads or.cables 5, shown individually as 5a and 5b, and at the negative terminals by interconnecting leads 7, shown individually as 7a and 7b. As shown, the battery pack 1 includes a positive output terminal 9 and a negative output terminal 11. The positive terminal 9 is connected to the positive interconnecting lead 5 through a positive terminal lead 10 and the negative terminal 11 is connected to the negative interconnecting lead 7 through a negative terminal lead 12.
Reference is next made to Fig. 2, which shows an equivalent circuit for the battery pack 1 of Fig. 1. In the equivalent circuit, the conductors for the interconnecting leads 5, 7 and terminals 9, 11 are replaced by resistive elements as shown in Fig. 2. The positive interconnecting leads 5a, 5b, .... are represented by respective resistors R1, R" RS, . . . Rzn-~ . Similarly, the negative interconnecting leads 7a, "7b, .... are represented by respective resistors Rz, R" R6, . .. Rz". The positive terminal lead 10 is represented by resistor R~2,.
and the negative terminal lead 12 is represented by resistor R~1. As also shown in Fig. 2, the battery modules 3 are represented by cells rl, r2, r3,... rn, respectively, where r1, r2, r3 represents the internal resistance of the respective battery module 3.
It is a feature of the present invention that the battery modules 3 are connected in parallel and the -interconnecting leads 5 and 7 have the same length so that w the charging current applied to the terminals 9, 11 is.

shared equally between the individual battery modules 3a, 3b, 3c. This feature of equally sharing the current is particularly important during the recharging of the battery modules 3, particularly, when a high rate or rapid charger is used, i.e. the charging rate for a battery module 3is greater than a 1C. The equal current sharing feature of the battery pack 1 ensures that the individual battery modules 3 are charged equally.
Referring again to Fig. 2, the overall resistance for each of the modules 3 in the battery pack 1 will be as f O110WS
ERl = Rci + ri + Ri + R3 + . . + RZn_1 + Rca ~'RZ - RCl + RZ + r2 + R3 + . . + R2n_1 + RCZ
FRn = R.cl + RZ + R~ + . . + R2n + rn +R~
As will be understood by one skilled in the art the rate of charging for batteries is affected by three primary factors. The internal resistance (i.e «r") of the module 3 is a function of charging current, state of charge in the battery and internal temperature of the battery.
The arrangement for the battery pack 1 according to the present invention addresses these factors to provide optimum charging of the individual modules 3 in the battery pack 1. Firstly, the battery pack 1 allows the modules 3 to be positioned in physically close relationship so that the modules 3 will be isothermal and this will minimize the temperature difference between modules 3 during charging.
The modules 3 are tightly grouped both physically and electrically, and as a result the same state of charge can be assumed for each module 3, and represented as:
rl = rz = . . . . - rn _ g _ It is a feature of the present invention that the interconnecting leads (i.e. cables) 5, 7, have the same "electrical length", that is, the same ohmic resistance, and the ohmic resistance is represented as:
R1 = RZ = . . - Rzn and R~l = R~Z = R~
Accordingly, the total DC resistance for each of n battery modules 3 is represented as follows:
ER = 2~R,~ + r + (n-1) ~R
Therefore, the resulting voltage drop across every module 3 in a group or battery pack 1 will be identical.
The battery pack 1 arrangement shown in Fig . 1 Was tested using three standard 12V battery modules (manufactured by OPTIMA) and connected in parallel according to the present invention. The battery pack 1 was successfully cycled through a series of more than a hundred high charge rate cycles. A high rate charge cycle is def fined to be greater than a iC rate on the battery module .
In this test, the battery pack 1 Was charged at 600A, divided among the three battery modules 3a, 3b, 3c with 200A each. The nominal capacity for each battery module 3, as rated by the manufacturer, was 56 Ahr giving approximately a 3.5C charge rate. It was found that the interconnection arrangement according to the present invention provided uniform charging conditions for each module 3 in the pack 1 throughout the testing cycle.
The present invention may be embodied in other specific forms Without departing from the spirit or essential characteristics thereof. Therefore, the presently discussed embodiments are considered to be illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (12)

WHAT IS CLAIMED IS:
1. A battery pack comprising:
(a) a plurality of battery modules, each of said battery modules having a positive terminal and a negative terminal;
(b) positive interconnecting cables for connecting the positive terminal of each of said battery modules;
(c) negative interconnecting cables for connecting the negative terminal of each of said battery modules;
(d) a negative output cable coupled to the negative terminal of one of said battery modules; and (e) a positive output cable coupled to the positive terminal of one of said battery modules, wherein said positive and negative interconnecting cables each have the same Ohmic resistance, and wherein said positive and negative output cables each have the same Ohmic resistance.
2. The battery pack as claimed in claim 1, wherein said positive and negative interconnecting cables each have the same length.
3. The battery pack as claimed in claim 1 or claim 2, wherein said positive and negative output cables each have the same length.
4. The battery pack as claimed in claim 2 or claim 3, wherein said positive and negative interconnecting cables each have the same gauge.
5. The battery pack as claimed in claim 3, wherein said positive and negative output cables each have the same gauge.
6. The battery pack as claimed in any one of claims 1 to 5, wherein adjacent battery modules are positioned in close proximity to each other in an isothermal zone.
7. The battery pack as claimed in claim 6, wherein said positive and negative interconnecting cables have a minimum length for spanning the distance between the respective positive and negative terminals on adjacent battery modules.
8. The battery pack as claimed in any one of claims 1 to 7, wherein said battery modules comprise rechargeable battery modules.
9. A method for forming a battery pack from a plurality of battery modules, said method comprising the steps of:
positioning the battery modules in close proximity to each other;
interconnecting the respective positive terminals on the battery modules with interconnecting cables of the same Ohmic resistance; and interconnecting the respective negative terminals on the battery modules with interconnecting cables of the same Ohmic resistance.
10. A battery pack comprising:
(a) a plurality of battery modules, each of said battery modules having a positive terminal and a negative terminal;
(b) positive interconnecting cables for connecting the positive terminal of each of said battery modules;
(c) negative interconnecting cables for connecting the negative terminal of each of said battery modules;
(d) a negative output cable coupled to the negative terminal of one of said battery modules; and (e) a positive output cable coupled to the positive terminal of one of said battery modules, wherein said positive and negative interconnecting cables each have the same Ohmic resistance.
11. The battery pack as claimed in claim 10, wherein adjacent battery modules are positioned in close proximity to each other in an isothermal zone.
12.. The battery pack as claimed in claim 11, wherein said battery modules comprise rechargeable battery modules.
CA002295760A 1997-06-25 1998-05-27 Battery pack and method for connecting battery modules Expired - Fee Related CA2295760C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US08/882,498 US5993992A (en) 1997-06-25 1997-06-25 Battery pack with connecting battery modules
US08/882,498 1997-06-25
PCT/CA1998/000514 WO1999000858A1 (en) 1997-06-25 1998-05-27 Battery pack and method for connecting battery modules

Publications (2)

Publication Number Publication Date
CA2295760A1 CA2295760A1 (en) 1999-01-07
CA2295760C true CA2295760C (en) 2007-03-13

Family

ID=25380722

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002295760A Expired - Fee Related CA2295760C (en) 1997-06-25 1998-05-27 Battery pack and method for connecting battery modules

Country Status (4)

Country Link
US (1) US5993992A (en)
AU (1) AU7517498A (en)
CA (1) CA2295760C (en)
WO (1) WO1999000858A1 (en)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7604896B2 (en) * 2005-03-16 2009-10-20 Ford Global Technologies, Llc High voltage battery assembly for a motor vehicle
CN101395781B (en) 2005-03-16 2011-09-14 福特全球技术公司 Power supply temperature sensor and system
MX2007011126A (en) * 2005-03-16 2007-11-13 Ford Global Tech Llc Power supply system.
BRPI0719878A2 (en) 2006-10-12 2014-06-10 Xpower Solutions Llc POWER SOURCE MODULES THAT HAVE A UNIFORM CC ENVIRONMENT
US7808131B2 (en) 2006-10-12 2010-10-05 Xtreme Power Inc. Precision battery pack circuits
US8237407B2 (en) * 2006-10-12 2012-08-07 Xtreme Power Inc. Power supply modules having a uniform DC environment
WO2009003083A1 (en) 2007-06-26 2008-12-31 The Coleman Company, Inc. Electrical appliance that utilizes multiple power sources
BRPI0820662A2 (en) 2007-11-27 2017-05-09 Xtreme Power Inc portable power supply having married resistance battery connections
US7915859B2 (en) * 2008-05-07 2011-03-29 Lg Electronics Inc. Apparatus and method for controlling power
EP2823521A1 (en) 2012-03-05 2015-01-14 Husqvarna AB Electrically symmetrical battery cell connector
JPWO2014024452A1 (en) * 2012-08-09 2016-07-25 三洋電機株式会社 Battery system, electric vehicle including the battery system, and power storage device
DE102018201355A1 (en) * 2018-01-30 2019-08-01 Robert Bosch Gmbh Battery module, battery pack containing this, as well as their use

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE347314A (en) *
JPS5073149A (en) * 1973-11-02 1975-06-17
US4217400A (en) * 1978-08-03 1980-08-12 General Electric Company Rechargeable electrochemical cell pack having overcurrent protection
US4371825A (en) * 1981-06-04 1983-02-01 Energy Development Associates, Inc. Method of minimizing the effects of parasitic currents
US4418127A (en) * 1981-11-23 1983-11-29 The United States Of America As Represented By The Secretary Of The Air Force Battery cell module
GB2136629B (en) * 1983-03-16 1986-11-19 South African Inventions Power storage battery
US4502000A (en) * 1983-07-19 1985-02-26 Energy Development Associates, Inc. Device for balancing parallel strings
GB2153136B (en) * 1984-01-20 1987-03-18 Lilliwyte Sa Temperature controlled na-s cell
JPS61206178A (en) * 1985-03-07 1986-09-12 Matsushita Electric Ind Co Ltd Series connection circuit for lithium secondary batteries
JP3003243B2 (en) * 1991-03-18 2000-01-24 ソニー株式会社 battery
US5191275A (en) * 1991-08-12 1993-03-02 Singhal Tara C Rechargeable battery pack device
FR2706083A1 (en) * 1993-06-02 1994-12-09 Texas Instruments France Improvements relating to battery unit assemblies.
US5418444A (en) * 1993-06-22 1995-05-23 Goldeneye Products, Inc. Automatic battery charge and discharge control system
US5358798A (en) * 1993-12-06 1994-10-25 Motorola, Inc. Battery assembly having a thermal fuse
US5496654A (en) * 1994-06-22 1996-03-05 Perkins; Bradley A. Secondary battery cell interconnection for protection from internal shorts
US5503948A (en) * 1994-08-02 1996-04-02 Microelectronics And Computer Technology Corporation Thin cell electrochemical battery system; and method of interconnecting multiple thin cells

Also Published As

Publication number Publication date
US5993992A (en) 1999-11-30
CA2295760A1 (en) 1999-01-07
WO1999000858A1 (en) 1999-01-07
AU7517498A (en) 1999-01-19

Similar Documents

Publication Publication Date Title
US7649336B2 (en) Power supply with bidirectional DC-DC converter
CN108604715B (en) Battery pack and charge-discharge control method
CA2295760C (en) Battery pack and method for connecting battery modules
US8093862B2 (en) Systems, apparatus and methods for battery charge management
US6465986B1 (en) Battery network with compounded interconnections
US8945757B2 (en) Battery pack having conductive line holders
US20090267565A1 (en) Method and system for cell equalization with charging sources and shunt regulators
US5773159A (en) Multicell configuration for lithium cells or the like
JP3572793B2 (en) Battery pack and method of manufacturing the battery pack
JP2001511638A (en) Equalization system and method for series connected energy storage devices
US6504342B2 (en) Battery pack
US20090309544A1 (en) Method and system for cell equalization with switched charging sources
JP4355515B2 (en) Battery module configuration method and battery module
CN104300644A (en) Multiloop charging method and system
WO2022014796A1 (en) Portable charging device for electric vehicle battery
US20090295336A1 (en) Individual-Charge and Merged-Discharge Battery Set
JPH08241705A (en) Battery pack
CN216288575U (en) Lithium ion battery formation clamp
KR20240145349A (en) Battery pack
KR102759864B1 (en) Hybrid Balancing Battery Management System, Battery Pack and EV including the same
CN220820187U (en) Multifunctional battery detection device and battery assembly
KR102931488B1 (en) Method for detecting defective battery cell and battery management system providing the same
KR102834351B1 (en) Battery management system
JP2024139751A (en) Battery pack
JP2786958B2 (en) Rechargeable battery charging circuit

Legal Events

Date Code Title Description
EEER Examination request
MKLA Lapsed

Effective date: 20160527